NIH has made 13 additional human embryonic stem cell lines eligible for federally funded research. The cell lines, which include four that were previously approved under the George W. Bush Administration, were posted to the NIH Stem Cell Registry on April 27. Two of those lines—H7 and H9—have been used extensively by researchers over the past few years. “Today’s action should provide welcome reassurance to the many researchers who have been working on lines . . .